int passcode(char *callin)
{
	int i = 0;
	char call[40];
	strncpy(call, callin, 30);
	unsigned int hash = 0x73e2;
	while (call[i]) {
		if (call[i] == '-')
			break;
		call[i] = toupper(call[i]);
		hash ^= call[i] << 8;
		if (call[i + 1] == 0)
			break;
		if (call[i + 1] == '-')
			break;
		call[i + 1] = toupper(call[i + 1]);
		hash ^= call[i + 1];
		i += 2;
	}
	hash = hash & 0x7fff;
	return hash;
}
